Problem with end_cap when combined with weighted edges

[balthasarbickel]

Consider the following MWE:
m <- matrix(c(1/4,2/4,1/4, 1/5,1/5,3/5, 3/6,1/6,2/6), ncol=3, byrow=T)
gg <- graph_from_adjacency_matrix(adjmatrix=m, weighted=TRUE, mode="directed", diag=T)

When using end_cap, as in the following, the edge widths are wrong:

ggraph(gg, layout = 'linear', circular=T) + 
	geom_edge_fan(aes(width=weight, label=round(weight,2)), 
		                   end_cap = circle(.5, 'cm'),
			           angle_calc='along', label_dodge=unit(-0.3, "cm")) + 	
	geom_edge_loop(aes(width=weight, direction=rep(c(30,270,150),3), label=round(weight,2)),
				    end_cap = circle(.5, 'cm'),
				    angle_calc='along', label_dodge=unit(-0.3, "cm")) +
		geom_node_point(size=12)

The edge widths are correct again if we remove the end_cap spec:

ggraph(gg, layout = 'linear', circular=T) + 
	geom_edge_fan(aes(width=weight, label=round(weight,2)), 
		                 #end_cap = circle(.5, 'cm'),
				   angle_calc='along', label_dodge=unit(-0.3, "cm")) + 	
	geom_edge_loop(aes(width=weight, direction=rep(c(30,270,150),3), label=round(weight,2)),
				 #end_cap = circle(.5, 'cm'),
				   angle_calc='along', label_dodge=unit(-0.3, "cm")) +
	geom_node_point(size=12)

[thomasp85]

Thanks for this - I'll look into it...

[justjacqueline]

I'm also having the same issue as @balthasarbickel. I am having the problem with my own data and when using the minimal example provided above.

I have igraph_1.1.2 and ggraph_1.0.2. However, my loaded version of cappedPathGrob does not seem to match that in 401e175, which was supposed to fix the plotting problem (I used getAnywhere(cappedPathGrob)). When I tried to add the file cappedPath.R, modified by @thomasp85 to my Global environment to see if it would fix the plotting issue, I got this error: Error in setChildren(x, gList(lines)) :
can only set 'children' for a "gTree" .

Perhaps I did something wrong when I tried this method of adding the functions to my working environment. I am quite new.

[malcolmbarrett]

@justjacqueline to get the dev version of a package on GitHub, you need to install it rather than loading a function in your global environment. Try devtools::install_github('thomasp85/ggraph'). You'll need the devtools package if you don't have it already (install.packages("devtools")).